Microsoft Security Advisory 2982792

In this article

Improperly Issued Digital Certificates Could Allow Spoofing

Published: July 10, 2014 | Updated: July 17, 2014

Version: 2.0

General Information

Executive Summary

Microsoft is aware of improperly issued SSL certificates that could be used in attempts to spoof content, perform phishing attacks, or perform man-in-the-middle attacks. The SSL certificates were improperly issued by the National Informatics Centre (NIC), which operates subordinate CAs under root CAs operated by the Government of India Controller of Certifying Authorities (CCA), which are CAs present in the Trusted Root Certification Authorities Store. This issue affects all supported releases of Microsoft Windows. Microsoft is not currently aware of attacks related to this issue.

The subordinate CA has been misused to issue SSL certificates for multiple sites, including Google web properties. These SSL certificates could be used to spoof content, perform phishing attacks, or perform man-in-the-middle attacks against web properties. The subordinate CAs may also have been used to issue certificates for other, currently unknown sites, which could be subject to similar attacks.

To help protect customers from potentially fraudulent use of this digital certificate, Microsoft is updating the Certificate Trust list (CTL) for all supported releases of Microsoft Windows to remove the trust of certificates that are causing this issue. For more information about these certificates, see the Frequently Asked Questions section of this advisory.

Recommendation. An automatic updater of revoked certificates is included in supported editions of Windows 8, Windows 8.1, Windows RT, Windows RT 8.1, Windows Server 2012, and Windows Server 2012 R2, and for devices running Windows Phone 8 or Windows Phone 8.1. For these operating systems or devices, customers do not need to take any action because the CTL will be updated automatically.

For systems running Windows Vista, Windows 7, Windows Server 2008, or Windows Server 2008 R2 that are using the automatic updater of revoked certificates (see Microsoft Knowledge Base Article 2677070 for details), customers do not need to take any action because the CTL will be updated automatically.

For customers running Windows Server 2003, Microsoft recommends that the 2982792 update be applied immediately using update management software, by checking for updates using the Microsoft Update service, or by downloading and applying the update manually. For more information, see the Suggested Actions section of this advisory.

Advisory FAQ

Why was this advisory updated on July 17, 2014?The advisory was updated on July 17, 2014 to announce the availability of update 2982792 for supported editions of Windows Server 2003. For more information see the Suggested Actions section of this advisory.

What is the scope of the advisory?The purpose of this advisory is to notify customers that National Informatics Centre (NIC) improperly issued SSL certificates for multiple sites including Google web properties. These SSL certificates could be used to spoof content, perform phishing attacks, or perform man-in-the-middle attacks against web properties. The subordinate CA may also have been used to issue certificates for other, currently unknown sites, which could be subject to similar attacks.

What caused the issue?A subordinate CA certificate was improperly issued by the National Informatics Centre (NIC), subordinated to the Government of India CA, which is a CA present in the Trusted Root Certification Authorities Store.

Does this update address any other digital certificates?Yes, in addition to addressing the certificates described in this advisory, this update is cumulative and includes digital certificates described in previous advisories:

What is cryptography?Cryptography is the science of securing information by converting it between its normal, readable state (called plaintext) and one in which the data is obscured (known as ciphertext).

In all forms of cryptography, a value known as a key is used in conjunction with a procedure called a crypto algorithm to transform plaintext data into ciphertext. In the most familiar type of cryptography, secret-key cryptography, the ciphertext is transformed back into plaintext using the same key. However, in a second type of cryptography, public-key cryptography, a different key is used to transform the ciphertext back into plaintext.

What is a digital certificate?In public-key cryptography, one of the keys, known as the private key, must be kept secret. The other key, known as the public key, is intended to be shared with the world. However, there must be a way for the owner of the key to tell the world who the key belongs to. Digital certificates provide a way to do this. A digital certificate is a tamperproof piece of data that packages a public key together with information about it (who owns it, what it can be used for, when it expires, and so forth).

What are certificates used for?Certificates are used primarily to verify the identity of a person or device, authenticate a service, or encrypt files. Normally you won’t have to think about certificates at all. You might, however, see a message telling you that a certificate is expired or invalid. In those cases you should follow the instructions in the message.

What is a certification authority (CA)?Certification authorities are the organizations that issue certificates. They establish and verify the authenticity of public keys that belong to people or other certification authorities, and they verify the identity of a person or organization that asks for a certificate.

What is a Certificate Trust List (CTL)?A trust must exist between the recipient of a signed message and the signer of the message. One method of establishing this trust is through a certificate, an electronic document verifying that entities or persons are who they claim to be. A certificate is issued to an entity by a third party that is trusted by both of the other parties. So, each recipient of a signed message decides if the issuer of the signer's certificate is trustworthy. CryptoAPI has implemented a methodology to allow application developers to create applications that automatically verify certificates against a predefined list of trusted certificates or roots. This list of trusted entities (called subjects) is called a certificate trust list (CTL). For more information, please see the MSDN article, Certificate Trust Verification.

What might an attacker do with these certificates?An attacker could use these certificates to spoof content, perform phishing attacks, or perform man-in-the-middle attacks against the following web properties:

google.com

mail.google.com

gmail.com

www.gmail.com

m.gmail.com

smtp.gmail.com

pop.gmail.com

imap.gmail.com

googlemail.com

www.googlemail.com

smtp.googlemail.com

pop.googlemail.com

imap.googlemail.com

gstatic.com

ssl.gstatic.com

www.static.com

encrypted-tbn1.gstatic.com

encrypted-tbn2.gstatic.com

login.yahoo.com

mail.yahoo.com

mail.yahoo-inc.com

fb.member.yahoo.com

login.korea.yahoo.com

api.reg.yahoo.com

edit.yahoo.com

watchlist.yahoo.com

edit.india.yahoo.com

edit.korea.yahoo.com

edit.europe.yahoo.com

edit.singapore.yahoo.com

edit.tpe.yahoo.com

legalredirect.yahoo.com

me.yahoo.com

open.login.yahooapis.com

subscribe.yahoo.com

edit.secure.yahoo.com

edit.client.yahoo.com

bt.edit.client.yahoo.com

verizon.edit.client.yahoo.com

na.edit.client.yahoo.com

au.api.reg.yahoo.com

au.reg.yahoo.com

profile.yahoo.com

static.profile.yahoo.com

openid.yahoo.com

What is a man-in-the-middle attack?A man-in-the-middle attack occurs when an attacker reroutes communication between two users through the attacker’s computer without the knowledge of the two communicating users. Each user in the communication unknowingly sends traffic to and receives traffic from the attacker, all the while thinking they are communicating only with the intended user.

What is Microsoft doing to help with resolving this issue?Although this issue does not result from an issue in any Microsoft product, we are nevertheless updating the CTL and providing an update to help protect customers. Microsoft will continue to investigate this issue and may make future changes to the CTL or release a future update to help protect customers.

After applying the update, how can I verify the certificates in the Microsoft Untrusted Certificates Store?For Windows Vista, Windows 7, Windows Server 2008, and Windows Server 2008 R2 systems that are using the automatic updater of revoked certificates (see Microsoft Knowledge Base Article 2677070 for details), and for Windows 8, Windows 8.1, Windows RT, Windows RT 8.1, Windows Server 2012, and Windows Server 2012 R2 systems, you can check the Application log in the Event Viewer for an entry with the following values:

Suggested Actions

Apply the update for supported releases of Microsoft Windows

An automatic updater of revoked certificates is included in supported editions of Windows 8, Windows 8.1, Windows RT, Windows RT 8.1, Windows Server 2012, and Windows Server 2012 R2, and for devices running Windows Phone 8 or Windows Phone 8.1. For these operating systems or devices, customers do not need to take any action because the CTL will be updated automatically.

For systems running Windows Vista, Windows 7, Windows Server 2008, or Windows Server 2008 R2 that are using the automatic updater of revoked certificates (see Microsoft Knowledge Base Article 2677070 for details), customers do not need to take any action because the CTL will be updated automatically.

For customers running Windows Server 2003, Microsoft recommends that the 2982792 update be applied immediately using update management software, by checking for updates using the Microsoft Update service, or by downloading and applying the update manually. See Microsoft Knowledge Base Article 2982792 for download links.

Users running Microsoft software should apply the latest Microsoft security updates to help make sure that their computers are as protected as possible. If you are not sure whether your software is up to date, visit Microsoft Update, scan your computer for available updates, and install any high-priority updates that are offered to you. If you have automatic updating enabled and configured to provide updates for Microsoft products, the updates are delivered to you when they are released, but you should verify that they are installed.

Acknowledgments

Microsoft thanks the following for working with us to help protect customers:

Disclaimer

The information provided in this advisory is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

Revisions

V1.0 (July 10, 2014): Advisory published.

V2.0 (July 17, 2014): Advisory revised to announce the availability of update 2982792 for supported editions of Windows Server 2003. For more information, see the Suggested Actions section of this advisory.

Page generated 2014-07-31 13:34Z-07:00.

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